Freeze-drying improves DNA yield from teeth

Rabiah A Rahmat; Melissa A Humphries; Adrian M T Linacre; Arif Malik; Nor A Saedon; Jeremy J Austin

doi:10.1016/j.forsciint.2021.110938

Freeze-drying improves DNA yield from teeth

Forensic Sci Int. 2021 Jul 29:326:110938. doi: 10.1016/j.forsciint.2021.110938. Online ahead of print.

Authors

Rabiah A Rahmat¹, Melissa A Humphries², Adrian M T Linacre³, Arif Malik⁴, Nor A Saedon⁵, Jeremy J Austin⁶

Affiliations

¹ Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia; School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5006, Australia. Electronic address: rabiahadaw@um.edu.my.
² School of Mathematical Sciences, Faculty of Engineering, Computer and Mathematical Sciences, University of Adelaide, Adelaide, South Australia 5006, Australia; ARC Centre of Excellence for Mathematical and Statistical Frontiers, University of Adelaide, Adelaide, South Australia, Australia. Electronic address: melissa.humphries@adelaide.edu.au.
³ College of Science and Engineering, Flinders University, Adelaide, South Australia 5042, Australia. Electronic address: adrian.linacre@flinders.edu.au.
⁴ School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5006, Australia. Electronic address: arif.malik@adelaide.edu.au.
⁵ Forensic DNA Division, Forensic Science Analysis Centre, Department of Chemistry, Selangor 46661, Malaysia. Electronic address: dora@kimia.gov.my.
⁶ Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5006, Australia. Electronic address: jeremy.austin@adelaide.edu.au.

PMID: 34343942
DOI: 10.1016/j.forsciint.2021.110938

Abstract

The common method of preparing teeth prior to DNA extraction involves cleaning, decontamination, drying and pulverisation. Moisture in post-mortem teeth can promote bacterial growth and hydrolytic damage that could contribute to DNA degradation, whilst also possibly reducing the efficiency of sample pulverisation and DNA release. Here we compared DNA extraction from pig teeth, with- and without freeze-drying, to examine the impact of removing moisture on DNA yield. Quantitative real-time polymerase chain reaction (qPCR) was used to quantify an 83 bp mitochondrial DNA fragment and two nuclear DNA fragments of 82 bp and 150 bp. The comparative results showed that sample preparation with freeze-drying resulted in a higher DNA yield without compromising the DNA quality. This study highlights the advantage of incorporating a freeze-drying to improve the DNA yield and minimising the loss of DNA during sample preparation of teeth.

Keywords: DNA extraction; Freeze-drying; Quantitative polymerase chain reaction; Sample preparation; Teeth.